Padlock



S. G. CALVELAGE.

PADLOCK.

APPLICATLON E'lLED DEc.20, 191s.

1,322,531. Panted NOV. 25, 19.19.

UTE STATES PATENT FFCE.

STEPHEN G. CALVELAGE, OF JAMESTOWN, NORTH DAKOTA.

PADLOCK.

Application led December 20, 1918.

To all whom it may concern:

Be it known that I, STEPHEN Gr. Cam/'EL- Aen, a citizen of the United States, residing at Jamestown, in the county of Stutsman and State of North Dakota, have invented certain new and useful Improvements in Padlocks, of which the following is a speciication.

This invention relates to padlocks, and more especially to those having a pivoted shackle and a movable latch coacting therewith; and the primary object of the invention is to produce a keyless padlock, where in special knowledge of the construction is necessary in order to unlock it.

This idea is carried out by forming the free ends of the shackle and the latch with hooks whose bills have their active faces undercut on special lines so that when they are engaged with each other` the special manipulation of parts in a certain or er is necessary to effect disengagement.

Details are set forth in the following specication and claims, and attention is invited to the drawings herewith, and in which- Figure 1 is an elevation of this padlock as it appears from the front.

Fig. 2 is a vertical sectional view through the parts as connected and indicating in dotted lines how the latch is disconnected from the shackle in the act of lopening the padlock.

The casing of this padlock is preferably rectangular and is herein shown as compris ing front and back plates 1 and 2 which are connected, and one of which has a flange provided at the top withV openings 3 and 4 for the shackle. The latter is indicated as a whole by the numeral 7, one end or arm passing` through the opening 3 and being pivoted within the casing as at 8 and the other end or arm adapted to pass through the opening t when the shackle is closed and the padlock is locked. To open the padlock. this arm must be unlocked` after which it is swung back on its pivot 8 in a manner well known and taken off the element E with which it is shown engaged in Fig. 2. rIhe keyhole 9 in the front plate 1 as indicated in Fig. 1 is merely to give the impression that the lock may be unlocked by use of the key, although such is not the case.

The free or operative arm of the shackle is provided near its end and in its inner Specification of Letters Patent.

Patented Nov. 25, 1919.

Serial No. 267,633.

side with a notch 10 of the shape best shown in Fig. 2 or in other words the end portion of this arm of the shackle constitutes a hook 13. It is essential that the bill of the hook which is the same as the active face of the notch shall be undercut as at 11, or in other words the active face stands in a plane which is ob-liquefto the line of movement of the end of the shackle. The extremity of the shackle is preferably tapered as indicated at 12. A spring 14 is shown in Fig. 2 as secured at one end vupon the bottom of the casing, its other or free end lying in the path of the tip of the shackle for a purpose yet to be explained. The latch 17 is shown in Fig. 2 as pivoted within the casing at 16 at one end, its other end being offset or headed as at 1S substantially in the shape of a hook and the active face of this hook being undercut so as to engage the undercut face 11 above described when the parts stand as herein shown. Stops 19 and 20 limit the movement of the latch, and these stops may be rivets connecting the front and rear plates of the latch.

With this construction, the action of the padlock is as follows.

Assuming that the device is locked as shown in full lines in Fig. 2, an unauthorized person drawing upward on the left arm of the shackle is resisted by the pivot 8. If he draws upward on the right arm of the shackle, movement is resist-ed by the engagement of the two parts 13 and 18. The normal path of movement of the free arm of the shackle which is that arm' remote from its pivot, is directly upward or vertical from the point of starting as shown, whereas the possible path of movement of the end of the latch is through an arc around its pivot 16, and as the paths are not coincident, one element may not be moved without the other. If the unauthorized person attempts to draw upward on both the arms of the shackle, he is resisted by both means. If he attempts to push the left arm downward, the pivot still resists. If he attempts to push the right arm downward, he may succeed to a limited extent, but when he draws upward the hook and head will rengage and resist. Manifestly he cannot use a key although the keyhole 9 will stand as an invitation to do so.

.But the authorized user who knows the trick will proceed as follows: First swinging the entire padlock as shown in the position indicated in dotted lines, he then presses on the right arm of the shackle to push its extremity 12 slightly inward as the spring 14 will permit,the notch disengages the head 18 at the free end of the latch, and the latter turns by gravity out of contact with the stop pin 2O and falls onto the stoppin 19, leaving the shackle entirely free to be swung aside and withdrawn from the element E. Attention is invited to the fact that even the skilful operator may not "bring about this result unless he tilts the Y as may prove expedient vand fall within the padlock so that gravity is used to cause the automatic movement of the latch; and even after he has tilted it, he must first move the shackle to destroy the interlocking engage- -ment of the undercut faces above described,

and which is maintained normally by the VVpressure ofthe spring.

When the lock is open and removed from the element E it must eventually be replaced. Ihis is brought about by passing the free end or arm through the element and bearing it into the ,opening 4. It is not Vnecessary now to tilt the device as indicated in dotted lines and in fact it is not desirable to do so. The beveled or tapered extremity 12 passes the beveled out side 'of the head 18 when the latch rests against the stop 20, and pushes the latch slightly aside until said end 12 strikes the spring 14 and bears it down a little. Just at this moment, the hooked head 18 drops into the notch 10 and then when pressure on the shackle 7 is reduced, the parts assume the position shown.Y

The foregoing description and the drawings have reference to what may be considered the preferred form of my invention. It is to be understood that I may make certain changes in constructionand combination of parts, materials, dimensions, et cetera,

scope of the appended claims.

I-Iaving thus fully described my invention, what I claim as new and desire to secure by Letters Patent `is 1. In a padlock, the combination with a casing, and shackle pivoted therein and having in one side of its free arm a notch whose active face is oblique to the line of movement of such arm; of a latch movably mounted in the casing and having a head adapted to engage the notch when V`the free arm of the shackleis in a certain position,

and yielding means within the casing for pressing said arm normally out of said position.

2. In a padlock, the combination with a casing, a shackle pivoted at one end therein Vand having` another arm downturned and notched on its underside'on a line oblique to the path of itsv movement, and a spring secured within said casing and'having its tip bearing normally upward on the last- Vnamed end of the shackle; of a latch vmovhaving at its Vother end a head shaped to fall intov said notch, when Vthe free arm Vof the shackle is inserted and the spring is depressed, and stopswithin the casing for A limiting the movement of said latch.

4.. A padlock comprising a casing, a shackle pivoted therein and having a hook on its free arm, a spring bearing said arm normally out of the casing, and a latch movably mounted in the easing and having a hook adapted to engage the hook of the shackle to lock the latter, the engaging faces of said hooks being oblique to Ytheinrespective paths of movement and on lines'preventing the retraction of the latch Vunless the shackle is first borne inward.

In testimony whereof I afliX my signature in presence of two witnesses.

STEPHEN G. CALVELAGE. f Vitnesses:

LINUS E. M1LLER,

l E. A. GRIswoLD. 

